What is /thread?
This gets used on messageboards / forums to signify that the previous post (or a post that has been quoted) is either of such high standard / very useful and answers the question of the original post / owns someone that the thread cannot possibly contain any post that's better.
USER 1: Hey guys, who do you reckon is the greatest rock band in the world.
USER 2: Black Sabbath
USER 3: /thread
Used in various forums to signify that this thread needs to be closed for various reasons
Thread title: Free Porn